I really did this with no real measurements. I used the folders as my guide and cut fabric that was about 1 inch longer than the folders. I folded the top edge of each pocket and double stitched for strength. Each pocket is about 2 inches shorter than the height of the folders also. I then sewed each pocket on again using the folder as a guide. I stitched 1/4 inch from the bottom edge of the pocket piece. After I sewed all of hem on I took another piece of fabric the same size as my backing fabric and placed them right side together and sewed around leaving a 3 inch opening at the top to turn right side out. I then top stitched along the top edge to close the opening. I folded it over about 1 inch and then sewed it down for a rod pocket. I used a dowel and ribbon to make the hanger.
You could also use large grommets like the commercial version to hang it on a pocket chart holder if you are a teacher. I hope to have a few in my shop soon.
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